1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Linux Socket Filter Data Structures 4 */ 5 #ifndef __LINUX_FILTER_H__ 6 #define __LINUX_FILTER_H__ 7 8 #include <stdarg.h> 9 10 #include <linux/atomic.h> 11 #include <linux/refcount.h> 12 #include <linux/compat.h> 13 #include <linux/skbuff.h> 14 #include <linux/linkage.h> 15 #include <linux/printk.h> 16 #include <linux/workqueue.h> 17 #include <linux/sched.h> 18 #include <linux/capability.h> 19 #include <linux/set_memory.h> 20 #include <linux/kallsyms.h> 21 #include <linux/if_vlan.h> 22 #include <linux/vmalloc.h> 23 #include <linux/sockptr.h> 24 #include <crypto/sha.h> 25 26 #include <net/sch_generic.h> 27 28 #include <asm/byteorder.h> 29 #include <uapi/linux/filter.h> 30 #include <uapi/linux/bpf.h> 31 32 struct sk_buff; 33 struct sock; 34 struct seccomp_data; 35 struct bpf_prog_aux; 36 struct xdp_rxq_info; 37 struct xdp_buff; 38 struct sock_reuseport; 39 struct ctl_table; 40 struct ctl_table_header; 41 42 /* ArgX, context and stack frame pointer register positions. Note, 43 * Arg1, Arg2, Arg3, etc are used as argument mappings of function 44 * calls in BPF_CALL instruction. 45 */ 46 #define BPF_REG_ARG1 BPF_REG_1 47 #define BPF_REG_ARG2 BPF_REG_2 48 #define BPF_REG_ARG3 BPF_REG_3 49 #define BPF_REG_ARG4 BPF_REG_4 50 #define BPF_REG_ARG5 BPF_REG_5 51 #define BPF_REG_CTX BPF_REG_6 52 #define BPF_REG_FP BPF_REG_10 53 54 /* Additional register mappings for converted user programs. */ 55 #define BPF_REG_A BPF_REG_0 56 #define BPF_REG_X BPF_REG_7 57 #define BPF_REG_TMP BPF_REG_2 /* scratch reg */ 58 #define BPF_REG_D BPF_REG_8 /* data, callee-saved */ 59 #define BPF_REG_H BPF_REG_9 /* hlen, callee-saved */ 60 61 /* Kernel hidden auxiliary/helper register. */ 62 #define BPF_REG_AX MAX_BPF_REG 63 #define MAX_BPF_EXT_REG (MAX_BPF_REG + 1) 64 #define MAX_BPF_JIT_REG MAX_BPF_EXT_REG 65 66 /* unused opcode to mark special call to bpf_tail_call() helper */ 67 #define BPF_TAIL_CALL 0xf0 68 69 /* unused opcode to mark special load instruction. Same as BPF_ABS */ 70 #define BPF_PROBE_MEM 0x20 71 72 /* unused opcode to mark call to interpreter with arguments */ 73 #define BPF_CALL_ARGS 0xe0 74 75 /* As per nm, we expose JITed images as text (code) section for 76 * kallsyms. That way, tools like perf can find it to match 77 * addresses. 78 */ 79 #define BPF_SYM_ELF_TYPE 't' 80 81 /* BPF program can access up to 512 bytes of stack space. */ 82 #define MAX_BPF_STACK 512 83 84 /* Helper macros for filter block array initializers. */ 85 86 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */ 87 88 #define BPF_ALU64_REG(OP, DST, SRC) \ 89 ((struct bpf_insn) { \ 90 .code = BPF_ALU64 | BPF_OP(OP) | BPF_X, \ 91 .dst_reg = DST, \ 92 .src_reg = SRC, \ 93 .off = 0, \ 94 .imm = 0 }) 95 96 #define BPF_ALU32_REG(OP, DST, SRC) \ 97 ((struct bpf_insn) { \ 98 .code = BPF_ALU | BPF_OP(OP) | BPF_X, \ 99 .dst_reg = DST, \ 100 .src_reg = SRC, \ 101 .off = 0, \ 102 .imm = 0 }) 103 104 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */ 105 106 #define BPF_ALU64_IMM(OP, DST, IMM) \ 107 ((struct bpf_insn) { \ 108 .code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \ 109 .dst_reg = DST, \ 110 .src_reg = 0, \ 111 .off = 0, \ 112 .imm = IMM }) 113 114 #define BPF_ALU32_IMM(OP, DST, IMM) \ 115 ((struct bpf_insn) { \ 116 .code = BPF_ALU | BPF_OP(OP) | BPF_K, \ 117 .dst_reg = DST, \ 118 .src_reg = 0, \ 119 .off = 0, \ 120 .imm = IMM }) 121 122 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */ 123 124 #define BPF_ENDIAN(TYPE, DST, LEN) \ 125 ((struct bpf_insn) { \ 126 .code = BPF_ALU | BPF_END | BPF_SRC(TYPE), \ 127 .dst_reg = DST, \ 128 .src_reg = 0, \ 129 .off = 0, \ 130 .imm = LEN }) 131 132 /* Short form of mov, dst_reg = src_reg */ 133 134 #define BPF_MOV64_REG(DST, SRC) \ 135 ((struct bpf_insn) { \ 136 .code = BPF_ALU64 | BPF_MOV | BPF_X, \ 137 .dst_reg = DST, \ 138 .src_reg = SRC, \ 139 .off = 0, \ 140 .imm = 0 }) 141 142 #define BPF_MOV32_REG(DST, SRC) \ 143 ((struct bpf_insn) { \ 144 .code = BPF_ALU | BPF_MOV | BPF_X, \ 145 .dst_reg = DST, \ 146 .src_reg = SRC, \ 147 .off = 0, \ 148 .imm = 0 }) 149 150 /* Short form of mov, dst_reg = imm32 */ 151 152 #define BPF_MOV64_IMM(DST, IMM) \ 153 ((struct bpf_insn) { \ 154 .code = BPF_ALU64 | BPF_MOV | BPF_K, \ 155 .dst_reg = DST, \ 156 .src_reg = 0, \ 157 .off = 0, \ 158 .imm = IMM }) 159 160 #define BPF_MOV32_IMM(DST, IMM) \ 161 ((struct bpf_insn) { \ 162 .code = BPF_ALU | BPF_MOV | BPF_K, \ 163 .dst_reg = DST, \ 164 .src_reg = 0, \ 165 .off = 0, \ 166 .imm = IMM }) 167 168 /* Special form of mov32, used for doing explicit zero extension on dst. */ 169 #define BPF_ZEXT_REG(DST) \ 170 ((struct bpf_insn) { \ 171 .code = BPF_ALU | BPF_MOV | BPF_X, \ 172 .dst_reg = DST, \ 173 .src_reg = DST, \ 174 .off = 0, \ 175 .imm = 1 }) 176 177 static inline bool insn_is_zext(const struct bpf_insn *insn) 178 { 179 return insn->code == (BPF_ALU | BPF_MOV | BPF_X) && insn->imm == 1; 180 } 181 182 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */ 183 #define BPF_LD_IMM64(DST, IMM) \ 184 BPF_LD_IMM64_RAW(DST, 0, IMM) 185 186 #define BPF_LD_IMM64_RAW(DST, SRC, IMM) \ 187 ((struct bpf_insn) { \ 188 .code = BPF_LD | BPF_DW | BPF_IMM, \ 189 .dst_reg = DST, \ 190 .src_reg = SRC, \ 191 .off = 0, \ 192 .imm = (__u32) (IMM) }), \ 193 ((struct bpf_insn) { \ 194 .code = 0, /* zero is reserved opcode */ \ 195 .dst_reg = 0, \ 196 .src_reg = 0, \ 197 .off = 0, \ 198 .imm = ((__u64) (IMM)) >> 32 }) 199 200 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */ 201 #define BPF_LD_MAP_FD(DST, MAP_FD) \ 202 BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD) 203 204 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */ 205 206 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM) \ 207 ((struct bpf_insn) { \ 208 .code = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE), \ 209 .dst_reg = DST, \ 210 .src_reg = SRC, \ 211 .off = 0, \ 212 .imm = IMM }) 213 214 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM) \ 215 ((struct bpf_insn) { \ 216 .code = BPF_ALU | BPF_MOV | BPF_SRC(TYPE), \ 217 .dst_reg = DST, \ 218 .src_reg = SRC, \ 219 .off = 0, \ 220 .imm = IMM }) 221 222 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */ 223 224 #define BPF_LD_ABS(SIZE, IMM) \ 225 ((struct bpf_insn) { \ 226 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS, \ 227 .dst_reg = 0, \ 228 .src_reg = 0, \ 229 .off = 0, \ 230 .imm = IMM }) 231 232 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */ 233 234 #define BPF_LD_IND(SIZE, SRC, IMM) \ 235 ((struct bpf_insn) { \ 236 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_IND, \ 237 .dst_reg = 0, \ 238 .src_reg = SRC, \ 239 .off = 0, \ 240 .imm = IMM }) 241 242 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */ 243 244 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF) \ 245 ((struct bpf_insn) { \ 246 .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \ 247 .dst_reg = DST, \ 248 .src_reg = SRC, \ 249 .off = OFF, \ 250 .imm = 0 }) 251 252 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */ 253 254 #define BPF_STX_MEM(SIZE, DST, SRC, OFF) \ 255 ((struct bpf_insn) { \ 256 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \ 257 .dst_reg = DST, \ 258 .src_reg = SRC, \ 259 .off = OFF, \ 260 .imm = 0 }) 261 262 /* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */ 263 264 #define BPF_STX_XADD(SIZE, DST, SRC, OFF) \ 265 ((struct bpf_insn) { \ 266 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD, \ 267 .dst_reg = DST, \ 268 .src_reg = SRC, \ 269 .off = OFF, \ 270 .imm = 0 }) 271 272 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */ 273 274 #define BPF_ST_MEM(SIZE, DST, OFF, IMM) \ 275 ((struct bpf_insn) { \ 276 .code = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM, \ 277 .dst_reg = DST, \ 278 .src_reg = 0, \ 279 .off = OFF, \ 280 .imm = IMM }) 281 282 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */ 283 284 #define BPF_JMP_REG(OP, DST, SRC, OFF) \ 285 ((struct bpf_insn) { \ 286 .code = BPF_JMP | BPF_OP(OP) | BPF_X, \ 287 .dst_reg = DST, \ 288 .src_reg = SRC, \ 289 .off = OFF, \ 290 .imm = 0 }) 291 292 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */ 293 294 #define BPF_JMP_IMM(OP, DST, IMM, OFF) \ 295 ((struct bpf_insn) { \ 296 .code = BPF_JMP | BPF_OP(OP) | BPF_K, \ 297 .dst_reg = DST, \ 298 .src_reg = 0, \ 299 .off = OFF, \ 300 .imm = IMM }) 301 302 /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */ 303 304 #define BPF_JMP32_REG(OP, DST, SRC, OFF) \ 305 ((struct bpf_insn) { \ 306 .code = BPF_JMP32 | BPF_OP(OP) | BPF_X, \ 307 .dst_reg = DST, \ 308 .src_reg = SRC, \ 309 .off = OFF, \ 310 .imm = 0 }) 311 312 /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */ 313 314 #define BPF_JMP32_IMM(OP, DST, IMM, OFF) \ 315 ((struct bpf_insn) { \ 316 .code = BPF_JMP32 | BPF_OP(OP) | BPF_K, \ 317 .dst_reg = DST, \ 318 .src_reg = 0, \ 319 .off = OFF, \ 320 .imm = IMM }) 321 322 /* Unconditional jumps, goto pc + off16 */ 323 324 #define BPF_JMP_A(OFF) \ 325 ((struct bpf_insn) { \ 326 .code = BPF_JMP | BPF_JA, \ 327 .dst_reg = 0, \ 328 .src_reg = 0, \ 329 .off = OFF, \ 330 .imm = 0 }) 331 332 /* Relative call */ 333 334 #define BPF_CALL_REL(TGT) \ 335 ((struct bpf_insn) { \ 336 .code = BPF_JMP | BPF_CALL, \ 337 .dst_reg = 0, \ 338 .src_reg = BPF_PSEUDO_CALL, \ 339 .off = 0, \ 340 .imm = TGT }) 341 342 /* Function call */ 343 344 #define BPF_CAST_CALL(x) \ 345 ((u64 (*)(u64, u64, u64, u64, u64))(x)) 346 347 #define BPF_EMIT_CALL(FUNC) \ 348 ((struct bpf_insn) { \ 349 .code = BPF_JMP | BPF_CALL, \ 350 .dst_reg = 0, \ 351 .src_reg = 0, \ 352 .off = 0, \ 353 .imm = ((FUNC) - __bpf_call_base) }) 354 355 /* Raw code statement block */ 356 357 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM) \ 358 ((struct bpf_insn) { \ 359 .code = CODE, \ 360 .dst_reg = DST, \ 361 .src_reg = SRC, \ 362 .off = OFF, \ 363 .imm = IMM }) 364 365 /* Program exit */ 366 367 #define BPF_EXIT_INSN() \ 368 ((struct bpf_insn) { \ 369 .code = BPF_JMP | BPF_EXIT, \ 370 .dst_reg = 0, \ 371 .src_reg = 0, \ 372 .off = 0, \ 373 .imm = 0 }) 374 375 /* Internal classic blocks for direct assignment */ 376 377 #define __BPF_STMT(CODE, K) \ 378 ((struct sock_filter) BPF_STMT(CODE, K)) 379 380 #define __BPF_JUMP(CODE, K, JT, JF) \ 381 ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF)) 382 383 #define bytes_to_bpf_size(bytes) \ 384 ({ \ 385 int bpf_size = -EINVAL; \ 386 \ 387 if (bytes == sizeof(u8)) \ 388 bpf_size = BPF_B; \ 389 else if (bytes == sizeof(u16)) \ 390 bpf_size = BPF_H; \ 391 else if (bytes == sizeof(u32)) \ 392 bpf_size = BPF_W; \ 393 else if (bytes == sizeof(u64)) \ 394 bpf_size = BPF_DW; \ 395 \ 396 bpf_size; \ 397 }) 398 399 #define bpf_size_to_bytes(bpf_size) \ 400 ({ \ 401 int bytes = -EINVAL; \ 402 \ 403 if (bpf_size == BPF_B) \ 404 bytes = sizeof(u8); \ 405 else if (bpf_size == BPF_H) \ 406 bytes = sizeof(u16); \ 407 else if (bpf_size == BPF_W) \ 408 bytes = sizeof(u32); \ 409 else if (bpf_size == BPF_DW) \ 410 bytes = sizeof(u64); \ 411 \ 412 bytes; \ 413 }) 414 415 #define BPF_SIZEOF(type) \ 416 ({ \ 417 const int __size = bytes_to_bpf_size(sizeof(type)); \ 418 BUILD_BUG_ON(__size < 0); \ 419 __size; \ 420 }) 421 422 #define BPF_FIELD_SIZEOF(type, field) \ 423 ({ \ 424 const int __size = bytes_to_bpf_size(sizeof_field(type, field)); \ 425 BUILD_BUG_ON(__size < 0); \ 426 __size; \ 427 }) 428 429 #define BPF_LDST_BYTES(insn) \ 430 ({ \ 431 const int __size = bpf_size_to_bytes(BPF_SIZE((insn)->code)); \ 432 WARN_ON(__size < 0); \ 433 __size; \ 434 }) 435 436 #define __BPF_MAP_0(m, v, ...) v 437 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a) 438 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__) 439 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__) 440 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__) 441 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__) 442 443 #define __BPF_REG_0(...) __BPF_PAD(5) 444 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4) 445 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3) 446 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2) 447 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1) 448 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__) 449 450 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__) 451 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__) 452 453 #define __BPF_CAST(t, a) \ 454 (__force t) \ 455 (__force \ 456 typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long), \ 457 (unsigned long)0, (t)0))) a 458 #define __BPF_V void 459 #define __BPF_N 460 461 #define __BPF_DECL_ARGS(t, a) t a 462 #define __BPF_DECL_REGS(t, a) u64 a 463 464 #define __BPF_PAD(n) \ 465 __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2, \ 466 u64, __ur_3, u64, __ur_4, u64, __ur_5) 467 468 #define BPF_CALL_x(x, name, ...) \ 469 static __always_inline \ 470 u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \ 471 typedef u64 (*btf_##name)(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \ 472 u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)); \ 473 u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)) \ 474 { \ 475 return ((btf_##name)____##name)(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\ 476 } \ 477 static __always_inline \ 478 u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)) 479 480 #define BPF_CALL_0(name, ...) BPF_CALL_x(0, name, __VA_ARGS__) 481 #define BPF_CALL_1(name, ...) BPF_CALL_x(1, name, __VA_ARGS__) 482 #define BPF_CALL_2(name, ...) BPF_CALL_x(2, name, __VA_ARGS__) 483 #define BPF_CALL_3(name, ...) BPF_CALL_x(3, name, __VA_ARGS__) 484 #define BPF_CALL_4(name, ...) BPF_CALL_x(4, name, __VA_ARGS__) 485 #define BPF_CALL_5(name, ...) BPF_CALL_x(5, name, __VA_ARGS__) 486 487 #define bpf_ctx_range(TYPE, MEMBER) \ 488 offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1 489 #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2) \ 490 offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1 491 #if BITS_PER_LONG == 64 492 # define bpf_ctx_range_ptr(TYPE, MEMBER) \ 493 offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1 494 #else 495 # define bpf_ctx_range_ptr(TYPE, MEMBER) \ 496 offsetof(TYPE, MEMBER) ... offsetof(TYPE, MEMBER) + 8 - 1 497 #endif /* BITS_PER_LONG == 64 */ 498 499 #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE) \ 500 ({ \ 501 BUILD_BUG_ON(sizeof_field(TYPE, MEMBER) != (SIZE)); \ 502 *(PTR_SIZE) = (SIZE); \ 503 offsetof(TYPE, MEMBER); \ 504 }) 505 506 /* A struct sock_filter is architecture independent. */ 507 struct compat_sock_fprog { 508 u16 len; 509 compat_uptr_t filter; /* struct sock_filter * */ 510 }; 511 512 struct sock_fprog_kern { 513 u16 len; 514 struct sock_filter *filter; 515 }; 516 517 /* Some arches need doubleword alignment for their instructions and/or data */ 518 #define BPF_IMAGE_ALIGNMENT 8 519 520 struct bpf_binary_header { 521 u32 pages; 522 u8 image[] __aligned(BPF_IMAGE_ALIGNMENT); 523 }; 524 525 struct bpf_prog { 526 u16 pages; /* Number of allocated pages */ 527 u16 jited:1, /* Is our filter JIT'ed? */ 528 jit_requested:1,/* archs need to JIT the prog */ 529 gpl_compatible:1, /* Is filter GPL compatible? */ 530 cb_access:1, /* Is control block accessed? */ 531 dst_needed:1, /* Do we need dst entry? */ 532 blinded:1, /* Was blinded */ 533 is_func:1, /* program is a bpf function */ 534 kprobe_override:1, /* Do we override a kprobe? */ 535 has_callchain_buf:1, /* callchain buffer allocated? */ 536 enforce_expected_attach_type:1, /* Enforce expected_attach_type checking at attach time */ 537 call_get_stack:1; /* Do we call bpf_get_stack() or bpf_get_stackid() */ 538 enum bpf_prog_type type; /* Type of BPF program */ 539 enum bpf_attach_type expected_attach_type; /* For some prog types */ 540 u32 len; /* Number of filter blocks */ 541 u32 jited_len; /* Size of jited insns in bytes */ 542 u8 tag[BPF_TAG_SIZE]; 543 struct bpf_prog_aux *aux; /* Auxiliary fields */ 544 struct sock_fprog_kern *orig_prog; /* Original BPF program */ 545 unsigned int (*bpf_func)(const void *ctx, 546 const struct bpf_insn *insn); 547 /* Instructions for interpreter */ 548 struct sock_filter insns[0]; 549 struct bpf_insn insnsi[]; 550 }; 551 552 struct sk_filter { 553 refcount_t refcnt; 554 struct rcu_head rcu; 555 struct bpf_prog *prog; 556 }; 557 558 DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key); 559 560 #define __BPF_PROG_RUN(prog, ctx, dfunc) ({ \ 561 u32 ret; \ 562 cant_migrate(); \ 563 if (static_branch_unlikely(&bpf_stats_enabled_key)) { \ 564 struct bpf_prog_stats *stats; \ 565 u64 start = sched_clock(); \ 566 ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func); \ 567 stats = this_cpu_ptr(prog->aux->stats); \ 568 u64_stats_update_begin(&stats->syncp); \ 569 stats->cnt++; \ 570 stats->nsecs += sched_clock() - start; \ 571 u64_stats_update_end(&stats->syncp); \ 572 } else { \ 573 ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func); \ 574 } \ 575 ret; }) 576 577 #define BPF_PROG_RUN(prog, ctx) \ 578 __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nop_func) 579 580 /* 581 * Use in preemptible and therefore migratable context to make sure that 582 * the execution of the BPF program runs on one CPU. 583 * 584 * This uses migrate_disable/enable() explicitly to document that the 585 * invocation of a BPF program does not require reentrancy protection 586 * against a BPF program which is invoked from a preempting task. 587 * 588 * For non RT enabled kernels migrate_disable/enable() maps to 589 * preempt_disable/enable(), i.e. it disables also preemption. 590 */ 591 static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog, 592 const void *ctx) 593 { 594 u32 ret; 595 596 migrate_disable(); 597 ret = __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nop_func); 598 migrate_enable(); 599 return ret; 600 } 601 602 #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN 603 604 struct bpf_skb_data_end { 605 struct qdisc_skb_cb qdisc_cb; 606 void *data_meta; 607 void *data_end; 608 }; 609 610 struct bpf_redirect_info { 611 u32 flags; 612 u32 tgt_index; 613 void *tgt_value; 614 struct bpf_map *map; 615 u32 kern_flags; 616 }; 617 618 DECLARE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info); 619 620 /* flags for bpf_redirect_info kern_flags */ 621 #define BPF_RI_F_RF_NO_DIRECT BIT(0) /* no napi_direct on return_frame */ 622 623 /* Compute the linear packet data range [data, data_end) which 624 * will be accessed by various program types (cls_bpf, act_bpf, 625 * lwt, ...). Subsystems allowing direct data access must (!) 626 * ensure that cb[] area can be written to when BPF program is 627 * invoked (otherwise cb[] save/restore is necessary). 628 */ 629 static inline void bpf_compute_data_pointers(struct sk_buff *skb) 630 { 631 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 632 633 BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb)); 634 cb->data_meta = skb->data - skb_metadata_len(skb); 635 cb->data_end = skb->data + skb_headlen(skb); 636 } 637 638 /* Similar to bpf_compute_data_pointers(), except that save orginal 639 * data in cb->data and cb->meta_data for restore. 640 */ 641 static inline void bpf_compute_and_save_data_end( 642 struct sk_buff *skb, void **saved_data_end) 643 { 644 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 645 646 *saved_data_end = cb->data_end; 647 cb->data_end = skb->data + skb_headlen(skb); 648 } 649 650 /* Restore data saved by bpf_compute_data_pointers(). */ 651 static inline void bpf_restore_data_end( 652 struct sk_buff *skb, void *saved_data_end) 653 { 654 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 655 656 cb->data_end = saved_data_end; 657 } 658 659 static inline u8 *bpf_skb_cb(struct sk_buff *skb) 660 { 661 /* eBPF programs may read/write skb->cb[] area to transfer meta 662 * data between tail calls. Since this also needs to work with 663 * tc, that scratch memory is mapped to qdisc_skb_cb's data area. 664 * 665 * In some socket filter cases, the cb unfortunately needs to be 666 * saved/restored so that protocol specific skb->cb[] data won't 667 * be lost. In any case, due to unpriviledged eBPF programs 668 * attached to sockets, we need to clear the bpf_skb_cb() area 669 * to not leak previous contents to user space. 670 */ 671 BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != BPF_SKB_CB_LEN); 672 BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != 673 sizeof_field(struct qdisc_skb_cb, data)); 674 675 return qdisc_skb_cb(skb)->data; 676 } 677 678 /* Must be invoked with migration disabled */ 679 static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog, 680 struct sk_buff *skb) 681 { 682 u8 *cb_data = bpf_skb_cb(skb); 683 u8 cb_saved[BPF_SKB_CB_LEN]; 684 u32 res; 685 686 if (unlikely(prog->cb_access)) { 687 memcpy(cb_saved, cb_data, sizeof(cb_saved)); 688 memset(cb_data, 0, sizeof(cb_saved)); 689 } 690 691 res = BPF_PROG_RUN(prog, skb); 692 693 if (unlikely(prog->cb_access)) 694 memcpy(cb_data, cb_saved, sizeof(cb_saved)); 695 696 return res; 697 } 698 699 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog, 700 struct sk_buff *skb) 701 { 702 u32 res; 703 704 migrate_disable(); 705 res = __bpf_prog_run_save_cb(prog, skb); 706 migrate_enable(); 707 return res; 708 } 709 710 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog, 711 struct sk_buff *skb) 712 { 713 u8 *cb_data = bpf_skb_cb(skb); 714 u32 res; 715 716 if (unlikely(prog->cb_access)) 717 memset(cb_data, 0, BPF_SKB_CB_LEN); 718 719 res = bpf_prog_run_pin_on_cpu(prog, skb); 720 return res; 721 } 722 723 DECLARE_BPF_DISPATCHER(xdp) 724 725 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog, 726 struct xdp_buff *xdp) 727 { 728 /* Caller needs to hold rcu_read_lock() (!), otherwise program 729 * can be released while still running, or map elements could be 730 * freed early while still having concurrent users. XDP fastpath 731 * already takes rcu_read_lock() when fetching the program, so 732 * it's not necessary here anymore. 733 */ 734 return __BPF_PROG_RUN(prog, xdp, BPF_DISPATCHER_FUNC(xdp)); 735 } 736 737 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog); 738 739 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog) 740 { 741 return prog->len * sizeof(struct bpf_insn); 742 } 743 744 static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog) 745 { 746 return round_up(bpf_prog_insn_size(prog) + 747 sizeof(__be64) + 1, SHA1_BLOCK_SIZE); 748 } 749 750 static inline unsigned int bpf_prog_size(unsigned int proglen) 751 { 752 return max(sizeof(struct bpf_prog), 753 offsetof(struct bpf_prog, insns[proglen])); 754 } 755 756 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog) 757 { 758 /* When classic BPF programs have been loaded and the arch 759 * does not have a classic BPF JIT (anymore), they have been 760 * converted via bpf_migrate_filter() to eBPF and thus always 761 * have an unspec program type. 762 */ 763 return prog->type == BPF_PROG_TYPE_UNSPEC; 764 } 765 766 static inline u32 bpf_ctx_off_adjust_machine(u32 size) 767 { 768 const u32 size_machine = sizeof(unsigned long); 769 770 if (size > size_machine && size % size_machine == 0) 771 size = size_machine; 772 773 return size; 774 } 775 776 static inline bool 777 bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default) 778 { 779 return size <= size_default && (size & (size - 1)) == 0; 780 } 781 782 static inline u8 783 bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default) 784 { 785 u8 access_off = off & (size_default - 1); 786 787 #ifdef __LITTLE_ENDIAN 788 return access_off; 789 #else 790 return size_default - (access_off + size); 791 #endif 792 } 793 794 #define bpf_ctx_wide_access_ok(off, size, type, field) \ 795 (size == sizeof(__u64) && \ 796 off >= offsetof(type, field) && \ 797 off + sizeof(__u64) <= offsetofend(type, field) && \ 798 off % sizeof(__u64) == 0) 799 800 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0])) 801 802 static inline void bpf_prog_lock_ro(struct bpf_prog *fp) 803 { 804 #ifndef CONFIG_BPF_JIT_ALWAYS_ON 805 if (!fp->jited) { 806 set_vm_flush_reset_perms(fp); 807 set_memory_ro((unsigned long)fp, fp->pages); 808 } 809 #endif 810 } 811 812 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr) 813 { 814 set_vm_flush_reset_perms(hdr); 815 set_memory_ro((unsigned long)hdr, hdr->pages); 816 set_memory_x((unsigned long)hdr, hdr->pages); 817 } 818 819 static inline struct bpf_binary_header * 820 bpf_jit_binary_hdr(const struct bpf_prog *fp) 821 { 822 unsigned long real_start = (unsigned long)fp->bpf_func; 823 unsigned long addr = real_start & PAGE_MASK; 824 825 return (void *)addr; 826 } 827 828 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap); 829 static inline int sk_filter(struct sock *sk, struct sk_buff *skb) 830 { 831 return sk_filter_trim_cap(sk, skb, 1); 832 } 833 834 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err); 835 void bpf_prog_free(struct bpf_prog *fp); 836 837 bool bpf_opcode_in_insntable(u8 code); 838 839 void bpf_prog_free_linfo(struct bpf_prog *prog); 840 void bpf_prog_fill_jited_linfo(struct bpf_prog *prog, 841 const u32 *insn_to_jit_off); 842 int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog); 843 void bpf_prog_free_jited_linfo(struct bpf_prog *prog); 844 void bpf_prog_free_unused_jited_linfo(struct bpf_prog *prog); 845 846 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags); 847 struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags); 848 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size, 849 gfp_t gfp_extra_flags); 850 void __bpf_prog_free(struct bpf_prog *fp); 851 852 static inline void bpf_prog_unlock_free(struct bpf_prog *fp) 853 { 854 __bpf_prog_free(fp); 855 } 856 857 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter, 858 unsigned int flen); 859 860 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog); 861 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog, 862 bpf_aux_classic_check_t trans, bool save_orig); 863 void bpf_prog_destroy(struct bpf_prog *fp); 864 865 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk); 866 int sk_attach_bpf(u32 ufd, struct sock *sk); 867 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk); 868 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk); 869 void sk_reuseport_prog_free(struct bpf_prog *prog); 870 int sk_detach_filter(struct sock *sk); 871 int sk_get_filter(struct sock *sk, struct sock_filter __user *filter, 872 unsigned int len); 873 874 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp); 875 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp); 876 877 u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); 878 #define __bpf_call_base_args \ 879 ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \ 880 __bpf_call_base) 881 882 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog); 883 void bpf_jit_compile(struct bpf_prog *prog); 884 bool bpf_jit_needs_zext(void); 885 bool bpf_helper_changes_pkt_data(void *func); 886 887 static inline bool bpf_dump_raw_ok(const struct cred *cred) 888 { 889 /* Reconstruction of call-sites is dependent on kallsyms, 890 * thus make dump the same restriction. 891 */ 892 return kallsyms_show_value(cred); 893 } 894 895 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, 896 const struct bpf_insn *patch, u32 len); 897 int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt); 898 899 void bpf_clear_redirect_map(struct bpf_map *map); 900 901 static inline bool xdp_return_frame_no_direct(void) 902 { 903 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 904 905 return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT; 906 } 907 908 static inline void xdp_set_return_frame_no_direct(void) 909 { 910 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 911 912 ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT; 913 } 914 915 static inline void xdp_clear_return_frame_no_direct(void) 916 { 917 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 918 919 ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT; 920 } 921 922 static inline int xdp_ok_fwd_dev(const struct net_device *fwd, 923 unsigned int pktlen) 924 { 925 unsigned int len; 926 927 if (unlikely(!(fwd->flags & IFF_UP))) 928 return -ENETDOWN; 929 930 len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN; 931 if (pktlen > len) 932 return -EMSGSIZE; 933 934 return 0; 935 } 936 937 /* The pair of xdp_do_redirect and xdp_do_flush MUST be called in the 938 * same cpu context. Further for best results no more than a single map 939 * for the do_redirect/do_flush pair should be used. This limitation is 940 * because we only track one map and force a flush when the map changes. 941 * This does not appear to be a real limitation for existing software. 942 */ 943 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, 944 struct xdp_buff *xdp, struct bpf_prog *prog); 945 int xdp_do_redirect(struct net_device *dev, 946 struct xdp_buff *xdp, 947 struct bpf_prog *prog); 948 void xdp_do_flush(void); 949 950 /* The xdp_do_flush_map() helper has been renamed to drop the _map suffix, as 951 * it is no longer only flushing maps. Keep this define for compatibility 952 * until all drivers are updated - do not use xdp_do_flush_map() in new code! 953 */ 954 #define xdp_do_flush_map xdp_do_flush 955 956 void bpf_warn_invalid_xdp_action(u32 act); 957 958 #ifdef CONFIG_INET 959 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk, 960 struct bpf_prog *prog, struct sk_buff *skb, 961 u32 hash); 962 #else 963 static inline struct sock * 964 bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk, 965 struct bpf_prog *prog, struct sk_buff *skb, 966 u32 hash) 967 { 968 return NULL; 969 } 970 #endif 971 972 #ifdef CONFIG_BPF_JIT 973 extern int bpf_jit_enable; 974 extern int bpf_jit_harden; 975 extern int bpf_jit_kallsyms; 976 extern long bpf_jit_limit; 977 978 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size); 979 980 struct bpf_binary_header * 981 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr, 982 unsigned int alignment, 983 bpf_jit_fill_hole_t bpf_fill_ill_insns); 984 void bpf_jit_binary_free(struct bpf_binary_header *hdr); 985 u64 bpf_jit_alloc_exec_limit(void); 986 void *bpf_jit_alloc_exec(unsigned long size); 987 void bpf_jit_free_exec(void *addr); 988 void bpf_jit_free(struct bpf_prog *fp); 989 990 int bpf_jit_add_poke_descriptor(struct bpf_prog *prog, 991 struct bpf_jit_poke_descriptor *poke); 992 993 int bpf_jit_get_func_addr(const struct bpf_prog *prog, 994 const struct bpf_insn *insn, bool extra_pass, 995 u64 *func_addr, bool *func_addr_fixed); 996 997 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp); 998 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other); 999 1000 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen, 1001 u32 pass, void *image) 1002 { 1003 pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen, 1004 proglen, pass, image, current->comm, task_pid_nr(current)); 1005 1006 if (image) 1007 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET, 1008 16, 1, image, proglen, false); 1009 } 1010 1011 static inline bool bpf_jit_is_ebpf(void) 1012 { 1013 # ifdef CONFIG_HAVE_EBPF_JIT 1014 return true; 1015 # else 1016 return false; 1017 # endif 1018 } 1019 1020 static inline bool ebpf_jit_enabled(void) 1021 { 1022 return bpf_jit_enable && bpf_jit_is_ebpf(); 1023 } 1024 1025 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp) 1026 { 1027 return fp->jited && bpf_jit_is_ebpf(); 1028 } 1029 1030 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog) 1031 { 1032 /* These are the prerequisites, should someone ever have the 1033 * idea to call blinding outside of them, we make sure to 1034 * bail out. 1035 */ 1036 if (!bpf_jit_is_ebpf()) 1037 return false; 1038 if (!prog->jit_requested) 1039 return false; 1040 if (!bpf_jit_harden) 1041 return false; 1042 if (bpf_jit_harden == 1 && capable(CAP_SYS_ADMIN)) 1043 return false; 1044 1045 return true; 1046 } 1047 1048 static inline bool bpf_jit_kallsyms_enabled(void) 1049 { 1050 /* There are a couple of corner cases where kallsyms should 1051 * not be enabled f.e. on hardening. 1052 */ 1053 if (bpf_jit_harden) 1054 return false; 1055 if (!bpf_jit_kallsyms) 1056 return false; 1057 if (bpf_jit_kallsyms == 1) 1058 return true; 1059 1060 return false; 1061 } 1062 1063 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size, 1064 unsigned long *off, char *sym); 1065 bool is_bpf_text_address(unsigned long addr); 1066 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type, 1067 char *sym); 1068 1069 static inline const char * 1070 bpf_address_lookup(unsigned long addr, unsigned long *size, 1071 unsigned long *off, char **modname, char *sym) 1072 { 1073 const char *ret = __bpf_address_lookup(addr, size, off, sym); 1074 1075 if (ret && modname) 1076 *modname = NULL; 1077 return ret; 1078 } 1079 1080 void bpf_prog_kallsyms_add(struct bpf_prog *fp); 1081 void bpf_prog_kallsyms_del(struct bpf_prog *fp); 1082 1083 #else /* CONFIG_BPF_JIT */ 1084 1085 static inline bool ebpf_jit_enabled(void) 1086 { 1087 return false; 1088 } 1089 1090 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog) 1091 { 1092 return false; 1093 } 1094 1095 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp) 1096 { 1097 return false; 1098 } 1099 1100 static inline int 1101 bpf_jit_add_poke_descriptor(struct bpf_prog *prog, 1102 struct bpf_jit_poke_descriptor *poke) 1103 { 1104 return -ENOTSUPP; 1105 } 1106 1107 static inline void bpf_jit_free(struct bpf_prog *fp) 1108 { 1109 bpf_prog_unlock_free(fp); 1110 } 1111 1112 static inline bool bpf_jit_kallsyms_enabled(void) 1113 { 1114 return false; 1115 } 1116 1117 static inline const char * 1118 __bpf_address_lookup(unsigned long addr, unsigned long *size, 1119 unsigned long *off, char *sym) 1120 { 1121 return NULL; 1122 } 1123 1124 static inline bool is_bpf_text_address(unsigned long addr) 1125 { 1126 return false; 1127 } 1128 1129 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value, 1130 char *type, char *sym) 1131 { 1132 return -ERANGE; 1133 } 1134 1135 static inline const char * 1136 bpf_address_lookup(unsigned long addr, unsigned long *size, 1137 unsigned long *off, char **modname, char *sym) 1138 { 1139 return NULL; 1140 } 1141 1142 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp) 1143 { 1144 } 1145 1146 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp) 1147 { 1148 } 1149 1150 #endif /* CONFIG_BPF_JIT */ 1151 1152 void bpf_prog_kallsyms_del_all(struct bpf_prog *fp); 1153 1154 #define BPF_ANC BIT(15) 1155 1156 static inline bool bpf_needs_clear_a(const struct sock_filter *first) 1157 { 1158 switch (first->code) { 1159 case BPF_RET | BPF_K: 1160 case BPF_LD | BPF_W | BPF_LEN: 1161 return false; 1162 1163 case BPF_LD | BPF_W | BPF_ABS: 1164 case BPF_LD | BPF_H | BPF_ABS: 1165 case BPF_LD | BPF_B | BPF_ABS: 1166 if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X) 1167 return true; 1168 return false; 1169 1170 default: 1171 return true; 1172 } 1173 } 1174 1175 static inline u16 bpf_anc_helper(const struct sock_filter *ftest) 1176 { 1177 BUG_ON(ftest->code & BPF_ANC); 1178 1179 switch (ftest->code) { 1180 case BPF_LD | BPF_W | BPF_ABS: 1181 case BPF_LD | BPF_H | BPF_ABS: 1182 case BPF_LD | BPF_B | BPF_ABS: 1183 #define BPF_ANCILLARY(CODE) case SKF_AD_OFF + SKF_AD_##CODE: \ 1184 return BPF_ANC | SKF_AD_##CODE 1185 switch (ftest->k) { 1186 BPF_ANCILLARY(PROTOCOL); 1187 BPF_ANCILLARY(PKTTYPE); 1188 BPF_ANCILLARY(IFINDEX); 1189 BPF_ANCILLARY(NLATTR); 1190 BPF_ANCILLARY(NLATTR_NEST); 1191 BPF_ANCILLARY(MARK); 1192 BPF_ANCILLARY(QUEUE); 1193 BPF_ANCILLARY(HATYPE); 1194 BPF_ANCILLARY(RXHASH); 1195 BPF_ANCILLARY(CPU); 1196 BPF_ANCILLARY(ALU_XOR_X); 1197 BPF_ANCILLARY(VLAN_TAG); 1198 BPF_ANCILLARY(VLAN_TAG_PRESENT); 1199 BPF_ANCILLARY(PAY_OFFSET); 1200 BPF_ANCILLARY(RANDOM); 1201 BPF_ANCILLARY(VLAN_TPID); 1202 } 1203 fallthrough; 1204 default: 1205 return ftest->code; 1206 } 1207 } 1208 1209 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, 1210 int k, unsigned int size); 1211 1212 static inline void *bpf_load_pointer(const struct sk_buff *skb, int k, 1213 unsigned int size, void *buffer) 1214 { 1215 if (k >= 0) 1216 return skb_header_pointer(skb, k, size, buffer); 1217 1218 return bpf_internal_load_pointer_neg_helper(skb, k, size); 1219 } 1220 1221 static inline int bpf_tell_extensions(void) 1222 { 1223 return SKF_AD_MAX; 1224 } 1225 1226 struct bpf_sock_addr_kern { 1227 struct sock *sk; 1228 struct sockaddr *uaddr; 1229 /* Temporary "register" to make indirect stores to nested structures 1230 * defined above. We need three registers to make such a store, but 1231 * only two (src and dst) are available at convert_ctx_access time 1232 */ 1233 u64 tmp_reg; 1234 void *t_ctx; /* Attach type specific context. */ 1235 }; 1236 1237 struct bpf_sock_ops_kern { 1238 struct sock *sk; 1239 u32 op; 1240 union { 1241 u32 args[4]; 1242 u32 reply; 1243 u32 replylong[4]; 1244 }; 1245 u32 is_fullsock; 1246 u64 temp; /* temp and everything after is not 1247 * initialized to 0 before calling 1248 * the BPF program. New fields that 1249 * should be initialized to 0 should 1250 * be inserted before temp. 1251 * temp is scratch storage used by 1252 * sock_ops_convert_ctx_access 1253 * as temporary storage of a register. 1254 */ 1255 }; 1256 1257 struct bpf_sysctl_kern { 1258 struct ctl_table_header *head; 1259 struct ctl_table *table; 1260 void *cur_val; 1261 size_t cur_len; 1262 void *new_val; 1263 size_t new_len; 1264 int new_updated; 1265 int write; 1266 loff_t *ppos; 1267 /* Temporary "register" for indirect stores to ppos. */ 1268 u64 tmp_reg; 1269 }; 1270 1271 struct bpf_sockopt_kern { 1272 struct sock *sk; 1273 u8 *optval; 1274 u8 *optval_end; 1275 s32 level; 1276 s32 optname; 1277 s32 optlen; 1278 s32 retval; 1279 }; 1280 1281 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len); 1282 1283 struct bpf_sk_lookup_kern { 1284 u16 family; 1285 u16 protocol; 1286 struct { 1287 __be32 saddr; 1288 __be32 daddr; 1289 } v4; 1290 struct { 1291 const struct in6_addr *saddr; 1292 const struct in6_addr *daddr; 1293 } v6; 1294 __be16 sport; 1295 u16 dport; 1296 struct sock *selected_sk; 1297 bool no_reuseport; 1298 }; 1299 1300 extern struct static_key_false bpf_sk_lookup_enabled; 1301 1302 /* Runners for BPF_SK_LOOKUP programs to invoke on socket lookup. 1303 * 1304 * Allowed return values for a BPF SK_LOOKUP program are SK_PASS and 1305 * SK_DROP. Their meaning is as follows: 1306 * 1307 * SK_PASS && ctx.selected_sk != NULL: use selected_sk as lookup result 1308 * SK_PASS && ctx.selected_sk == NULL: continue to htable-based socket lookup 1309 * SK_DROP : terminate lookup with -ECONNREFUSED 1310 * 1311 * This macro aggregates return values and selected sockets from 1312 * multiple BPF programs according to following rules in order: 1313 * 1314 * 1. If any program returned SK_PASS and a non-NULL ctx.selected_sk, 1315 * macro result is SK_PASS and last ctx.selected_sk is used. 1316 * 2. If any program returned SK_DROP return value, 1317 * macro result is SK_DROP. 1318 * 3. Otherwise result is SK_PASS and ctx.selected_sk is NULL. 1319 * 1320 * Caller must ensure that the prog array is non-NULL, and that the 1321 * array as well as the programs it contains remain valid. 1322 */ 1323 #define BPF_PROG_SK_LOOKUP_RUN_ARRAY(array, ctx, func) \ 1324 ({ \ 1325 struct bpf_sk_lookup_kern *_ctx = &(ctx); \ 1326 struct bpf_prog_array_item *_item; \ 1327 struct sock *_selected_sk = NULL; \ 1328 bool _no_reuseport = false; \ 1329 struct bpf_prog *_prog; \ 1330 bool _all_pass = true; \ 1331 u32 _ret; \ 1332 \ 1333 migrate_disable(); \ 1334 _item = &(array)->items[0]; \ 1335 while ((_prog = READ_ONCE(_item->prog))) { \ 1336 /* restore most recent selection */ \ 1337 _ctx->selected_sk = _selected_sk; \ 1338 _ctx->no_reuseport = _no_reuseport; \ 1339 \ 1340 _ret = func(_prog, _ctx); \ 1341 if (_ret == SK_PASS && _ctx->selected_sk) { \ 1342 /* remember last non-NULL socket */ \ 1343 _selected_sk = _ctx->selected_sk; \ 1344 _no_reuseport = _ctx->no_reuseport; \ 1345 } else if (_ret == SK_DROP && _all_pass) { \ 1346 _all_pass = false; \ 1347 } \ 1348 _item++; \ 1349 } \ 1350 _ctx->selected_sk = _selected_sk; \ 1351 _ctx->no_reuseport = _no_reuseport; \ 1352 migrate_enable(); \ 1353 _all_pass || _selected_sk ? SK_PASS : SK_DROP; \ 1354 }) 1355 1356 static inline bool bpf_sk_lookup_run_v4(struct net *net, int protocol, 1357 const __be32 saddr, const __be16 sport, 1358 const __be32 daddr, const u16 dport, 1359 struct sock **psk) 1360 { 1361 struct bpf_prog_array *run_array; 1362 struct sock *selected_sk = NULL; 1363 bool no_reuseport = false; 1364 1365 rcu_read_lock(); 1366 run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]); 1367 if (run_array) { 1368 struct bpf_sk_lookup_kern ctx = { 1369 .family = AF_INET, 1370 .protocol = protocol, 1371 .v4.saddr = saddr, 1372 .v4.daddr = daddr, 1373 .sport = sport, 1374 .dport = dport, 1375 }; 1376 u32 act; 1377 1378 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, BPF_PROG_RUN); 1379 if (act == SK_PASS) { 1380 selected_sk = ctx.selected_sk; 1381 no_reuseport = ctx.no_reuseport; 1382 } else { 1383 selected_sk = ERR_PTR(-ECONNREFUSED); 1384 } 1385 } 1386 rcu_read_unlock(); 1387 *psk = selected_sk; 1388 return no_reuseport; 1389 } 1390 1391 #if IS_ENABLED(CONFIG_IPV6) 1392 static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol, 1393 const struct in6_addr *saddr, 1394 const __be16 sport, 1395 const struct in6_addr *daddr, 1396 const u16 dport, 1397 struct sock **psk) 1398 { 1399 struct bpf_prog_array *run_array; 1400 struct sock *selected_sk = NULL; 1401 bool no_reuseport = false; 1402 1403 rcu_read_lock(); 1404 run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]); 1405 if (run_array) { 1406 struct bpf_sk_lookup_kern ctx = { 1407 .family = AF_INET6, 1408 .protocol = protocol, 1409 .v6.saddr = saddr, 1410 .v6.daddr = daddr, 1411 .sport = sport, 1412 .dport = dport, 1413 }; 1414 u32 act; 1415 1416 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, BPF_PROG_RUN); 1417 if (act == SK_PASS) { 1418 selected_sk = ctx.selected_sk; 1419 no_reuseport = ctx.no_reuseport; 1420 } else { 1421 selected_sk = ERR_PTR(-ECONNREFUSED); 1422 } 1423 } 1424 rcu_read_unlock(); 1425 *psk = selected_sk; 1426 return no_reuseport; 1427 } 1428 #endif /* IS_ENABLED(CONFIG_IPV6) */ 1429 1430 #endif /* __LINUX_FILTER_H__ */ 1431